Climate: Temperatures and Precipitation

Read the previous post in the map-building series: And Then It Exploded.

So, a while ago I started the map-building series as a backlash against All Those Authors that get it Wrong, and as an attempt to prevent that happening in the future. I've talked about the very fundamental stuff - the underlying structure of the world, the fun you can have with hotspots and volcanos - and have developed a few rules to keep you on the right track:

- Lesson #0 in Map-Building: Always have a reason.
- Lesson #1 in Map Building: The mountains are where things crash together. So are the volancos and the earthquakes.
- Lesson #2 in Map Building: You need to have a reason for where you put things on your map. But you can pretty much invent a reason for anything.


Today, we're going to move on to above-surface stuff, and look at the basics of climate. Two things form the fundamental basis of all climate: temperature, and precipitation. You can get hot dry climates (like deserts), hot wet climates (like rainforests), warm dry, warm wet, temperate regions that have four distinct seasons and varying rainfall in each, cold wet climates, cold dry climates, climates that are prone to snow and forms of precipitation other than plain rain.

Your plain average rain, however, isn't really plain or average. It can be pure or acidic to various degrees, it can be cold rain or warm rain, come in torrential downpours or gently soaking drizzle. Acidic rain is found in areas of high pollution or places downwind from high-pollution areas; pure rain is often found in low population density areas, but not always, because these places can be receiving pollution from other areas. Torrential rain is most usually found in the tropics; hurricanes need the right mix of airflow and water; thunderstorms need a cold front meeting a bank of warm air; drizzle often accompanies lower temperatures; and so the list goes on.


You can get so caught up in the fascinating minutia of weather - well, at least, I could - that you forget your story is actually supposed to ever be anything more than an excuse to build a really spiffy, perfectly logical world. I don't recommend this.

The amount of worldbuilding you DO want to do is up to you, but remember:

1) More worldbuilding makes your world seem more real.

2) Most of your worldbuilding won't make it directly into your novel, so it can be a waste of time.

and most importantly,

3) ALL worldbuilding should serve one aim: to increase conflict in your story. If you can't think of a way for it to increase conflict, you're pretty much wasting your time.

I mean, sure, it's important to know what kind of clothes your MC wears, and whether or not their society could actually legitimately make silk stockings - but this all matters a lot more to your reader if it's in some way related to the conflict, like your MC needs to masquerade as an aristocrat from another country only can't get her hands on the kind of stockings they wear, or something. Be creative. Make it matter.

And so to round off on climates: Do know your climate, because it will affect how your people live. More on that later. But don't feel you need to obsess. Most climates exist in most regions of the world, with the exception being the poles and the equator. Mountain ranges or lack thereof, ocean currents and whether they are hot or cold, costalness or continentality, prevailing winds - these are the four key things that will determine your climate. But really, weather is so complicated that even now we can't accurately predict it more than about four days out. So you know. As long as your climate is within the bounds of plausibility, most readers won't try to kill you for them.

With one exception. Please, please, please, don't try to make your poles hot and your equator cold for no reason better than 'to be different'. This will result in you being hunted down and smacked over the head with some basic physics.

Why?

Because the poles are, by the very nature of a ROUND planet, further away from the sun. The equator is closest. Ergo, unless you have some sort of fancy magic field that reverses the effect of the sun, your poles will be colder and your equator hotter.

And, for the love of peace, please have a round planet unless you're writing fantasy and have a deliberate reason for not making it so (and making it, say, a Disc carried by elephants on the back of a turtle). Gravity + spinning = round world.

Note also that it's the TILT of the earth's axis that gives us seasons; straight axis, no seasons. Bear that in mind when designing both round planets and especially non-round planets. If you're not round and/or you have no tilt, will you have seasons, or will your climates be stable?

Lesson #3 in Map Building: In the middle, things are grey and you can do what you like. At the edges, things have a reason. Don't mess with this, unless you have a very good reason.

Tune in next time for more on humanity's favourite liquid: water!